Solve these two problems. Use the product rule to show that t-derivative of the complex-valued function…

Solve these two problems.
Use the product rule to show that t-derivative of the complex-valued function f(t) = eat (cos bt + i sin bt) = e(a+bi)t is the function f(t) multiplied by a + bi. Use the previous result to find integration formulas for the real and imaginary parts of ſ f(t)dt.